package main

import (
	"context"
	"errors"
	"fmt"
	"git.entr0py.de/garionion/ffmpeg-playout/api"
	"git.entr0py.de/garionion/ffmpeg-playout/playout"
	"git.entr0py.de/garionion/ffmpeg-playout/store"
	"github.com/ilyakaznacheev/cleanenv"
	"google.golang.org/grpc"
	"log"
	"net"
	"time"
)

type server struct {
	api.UnimplementedPlayoutServer
	*store.Store
}

type Config struct {
	Outputs               []string `yaml:"outputs"`
	Address               string   `yaml:"address" env:"ADDRESS" env-default:":3000"`
	DefaultDuration       string   `yaml:"default_duration" env:"DEFAULT_DURATION" env-default:"15"`
	PlayoutScript         string   `yaml:"playoutscript"`
	PlayoutScriptPath     string   `yaml:"playoutscriptpath" env:""`
	ProgressDir           string   `yaml:"tmpdir"`
	OutputFormat          string   `yaml:"outputFormat"`
	PrometheusPushGateway string   `yaml:"prometheusPushGateway"`
}

func (g *server) SchedulePlayout(ctx context.Context, job *api.Job) (*api.ScheduledJob, error) {
	var p *playout.Job

	if job.Source == "" {
		return nil, errors.New("Got Empty Source. I can't play »Nothing«")
	}

	var output string
	newPlayoutJob := new(playout.Job)
	g.Store.RLock()
	olPlayoutJob, playoutExists := g.Store.Playouts[job.ID]
	g.Store.RUnlock()
	if playoutExists {
		p = olPlayoutJob
	} else {
		p = newPlayoutJob
		p.ControlChannel = make(chan string)
	}

	p.ID = job.ID
	p.Source = job.Source
	p.Version = job.Version
	p.StartAt = job.StartAt.AsTime()
	p.StopAt = job.StopAt.AsTime()
	if p.StopAt.IsZero() {
		p.StopAt = p.StartAt.Add(g.Store.DefaultDuration)
	}

	if playoutExists {
		p.ControlChannel <- "reschedule"
		output = p.Output
	} else {
		var err error

		g.Store.Lock()
		output, err = g.Store.AddPlayout(p)
		g.Store.Unlock()
		if err != nil {
			return nil, fmt.Errorf("can not schedule playout: %s", err)
		}
	}

	scheduledJob := &api.ScheduledJob{
		ID:      p.ID,
		Port:    output,
		Version: p.Version,
	}

	if !playoutExists {
		go func() {
			log.Printf("Start Scheduling %v", p.ID)
		Waiting:
			for {
				select {
				case ctrlMsg := <-p.ControlChannel:
					log.Printf("%d Control Message: %s", p.ID, ctrlMsg)
					continue
				case <-time.After(time.Until(p.StartAt)):
					break Waiting
				}
			}
			p.Playout(g.Store.Config)
			g.Store.DeletePlayout(p.ID)
		}()
	}

	return scheduledJob, nil
}

var cfg Config

func main() {
	// TODO configure config file path via cmd parameter
	if err := cleanenv.ReadConfig("config.yml", &cfg); err != nil {
		log.Fatal("No configfile: ", err)
	}

	s, err := store.NewStore(cfg.Outputs, cfg.DefaultDuration, cfg.PlayoutScriptPath, cfg.PlayoutScript, cfg.ProgressDir, cfg.PrometheusPushGateway, cfg.OutputFormat)
	if err != nil {
		log.Fatal("Failed to init Store: ", err.Error())
	}
	server := &server{
		Store: s,
	}

	ln, err := net.Listen("tcp", cfg.Address)
	if err != nil {
		log.Fatal(err)
	}

	g := grpc.NewServer()
	api.RegisterPlayoutServer(g, server)
	log.Fatalf("failed to serve: %v", g.Serve(ln))
}